Typewriter escapement control mechanism



'July 31; 1945.7.

'-TYPEWRITER E'scAPEMENT CNTBQLQKMECHANISM original Filed Aprgl 25, 194i# Y Patented July 31, 1945 OFFICE TYPEWRITER ESCAPEMENT CONTROL MECHANISM Halla M. Harrison, Portland, Oreg.

substituted for abandoned application Serial No.

390,231, April 25, 1941. This application December 7, 1943, Serial No. 513,251

1 Claim.

This invention relates to improvements in typewriters and, more particularly, to a mechanism to be either built into a typewriteror to be attached thereto as an accessory to render the machine capable of writing in syllables, as well as in individual letters.

This application is a substitute for my application iiled April 25, 1941, Serial No. 390,231.

The invention includes a plurality of typeheads carrying the conventionalsingle letter or figure and also pairs, or syllables of letters, so that through the medium of my invention, 1 am able to selectively write single letters in the conventional manner, or write in syllables in a manner somewhat similar to variouswellknown machines for writing shorthand in syllabic form.

A further object of the invention is to provide a mechanism of this character which is readily adaptable to a typewriter to render its operation similar to that of the above mentioned type of machine so that dictation may be given direct to an. operator of the typewriter.

These and other objects will appear as my invention is more fully hereinafter described in the following specification', illustrated in the accompanying drawing, and ilnally pointed out in the appended claim. Y Y

In the drawing? Figure 1 is an elevation of a plurality of typeheads arranged side by side in the usual manner and carrying letters arranged in syllables at their upper ends and single letters at their lower ends.

Figure 2 is a somewhat diagrammatic view in perspective showing my invention operatively connected with the escapement mechanism of a conventional typewriter.

. Figure 3 is a view similar to Figure 2 showing the mechanism of theinvention moved into a position to operate only the double letters of the type-heads.

Figure 4 is a diagram illustrating directions of movement of certain parts of the mechanism when set for writing in double letters.

Referring now more particularly to the drawing:

In Figure 2, reference numeral I indicates a type key pivotally mounted, as at 2, in the conventional manner to a typewriter and connected by a link 3 with a type lever 4, pivotally mounted, as at l, in the conventional manner. The upper end of the type lever is formed with a type-head 6 made in accordance with my invention and as illustrated in Figure l, wherein the upper portion and II, mounted in any suitable manner to the frame work I2 of the typewriter. Secured to the shaft 9 near one of its ends, as at I3, is a shifting of each type-head is formed with pairs of letters, 6b

lever I4 provided at vits outermost end with a shift key I5. The opposite end of the lever I4 is pivotally connected, as at I6, with a link I1 which may or may not be connected with the conventional shifting mechanism.

Secured to the shaft 9 and rotatable therewith is a leverIB whose free end is adjustably attached by means of nuts, I9 and 20, to the threaded ends of links, 2l and 22', respectively. The upper end of the link 2l is pivotally connected, as at 23, to one arm of a toggle 24, whose one outer end is pivotally connected, as at 25, to a lever or bell crank 26, which is pivotally connected, as at 21, to a shaft 28 journaled in bearings 36. The arm 3I of the bell crank 26 is pivotally connected to one end of a toggle arm 32 whose inner end is pivotally connected, as at 33, to the inner end of the oppositey arm-34 ofthe toggle and-also to the upper end of the link 22. The outer end of the arm 34 is connected as at 35, to a lever 36 which is attached, as at 31, to a shaft 36 journalled in bearings 39. The uppermost end of the lever 36 is connected, as at 40, to a link 4I whose opposite end connects, as at 42, to the lower end of an arm 43 depending from a plate 44. The plate carries two pawls, and 45A for intermittent and alternate engagement with an escapement wheel 46 which rotates in the direction of the arrow. The plate 44 is swingably'mounted by its pintles 41 in bearings 48.`

The pawl 45A may be formed integral with the plate 44, or attached to it as is the pawl 45. The pawl 45 is arranged in advance of the pawl 45A, a distance equal to the width of one tooth on the wheel 46. Both pawls are spaced apart lat-- erally, so that upon swingingthe plate 44, they will alternately engage the teeth of the escapement wheel. For example, in the position shown. the pawl 45 is engaged with one tooth of the wheel, while pawl 45A is out of engagement. Upon swinging the plate 44 to the left, as viewed in Figure 2, the pawl 45 will be taken out of engagement with the tooth in contact with it and allow that tooth to move around into contact withy the pawl 45A, which has been brought into the path of movement of the tooth by the swinging of the plate. The movement of one tooth from the rst pawl to the second allows escapement of the carriage (not shown) for one-half space. and this is done by the downward movement of the type key I. Swinging the plate 44 in an opposite direction by the upward movement of the type key allows said tooth to pass the pawl 45A, and at the same time moves the pawl 45 into position to meet the next tooth. Thus a complete down and up stroke of the type key I, allows the carriage to shift one full space.

'The inner ends of the toggle arms, 24 and 32, are formed with curved extensions, 49 and 50, respectively, adapted for engagement with pins, I and 52, respectively, carried by their companion arms to form limit stops for the upward movement of toggle 24 and downward movement of the toggle 32. In other words, the toggle 24 may only move downwardly from a horizontal position; and the toggle 32 may only move upwardly from a horizontal position.

The upper end of the vertical leg of the bell crank 26, to which the arm of the toggle 24 is attached, as at 25, is formed integr-a1 with, or may be secured to an escapement 53, arranged in the path of movement of a projection '54 formed on the type lever 4 which, upon its upward swing caused by a downward movement of the type key I, strikes the anvil and moves it inwardly. This movement through the aligned arms of the toggle 24, imparts inward movement of the link 4I by rocking the lever 36 around its shaft 38.

The inward movement of the link 4I rocks the plate 44 outwardly or to the left to allow escapement of the wheel 46, a distance of one tooth, as aforesaid. Then on the upward stroke of the type key, the wheel again escapes the distance of one tooth. By this arrangement, I am able to type with the single letters 8 in the conventional manner.

When it is desired to print in syllables, I move the shift key I4 downwardly which, through the downward swing of the arm I8 and the links 2| and 22, I collapse the arms of the toggle 24 and, at the same time, move the arms of the toggle 32 downwardly into a straight line to serve as a solid link. (See Figure 3). The toggle 24 is thus rendered inoperative, and the lever 36 and arm 4I are actuated only by the toggle 32 by inward movement of the anvil 53 caused by striking the type key and swinging the type lever 4 into contact with the anvil to rock the bell crank 26 around its pivot 21.

As previously stated, for writing with the syllables, it is necessary to allow a double escapement of the platen; and, accordingly, it is necessary that two teeth on the escapement wheel 46 pass the pawls 45 and 45A. To accomplish this, I swing the plate 44 inwardly and outwardly on one down stroke of the type key, and inwardly and outwardly on the up stroke of the type key.

The movement imparted to the now straightened toggle 32 is best illustrated diagrammatically in Figure 4, wherein 3l is the leg of the bell crank 26, and 32 is the toggle.' Upon movement of the anvil in the direction indicated by the arrow, the arm of the bell crank in its downward swing moves outwardly, then inwardly, a distance indicated at which moves the toggle, its related parts, and the plate 44 inwardly and outwardly to permit escapement of one tooth of wheel 46. On the up stroke of the type key I, which causes the bell crank arm 3l tovreturnto its original position, it moves the toggle outwardly, then inwardly, the same distance of travel as caused by the down stroke of the type key. This second inward and outward movement of the plate 44 allows another tooth to pass the pawls which thus allow the carriage to move two spaces to accommodate the syllabic type.

By means of the mechanism above described, I am able to quickly shift the mechanism for writing with single or double letters by merely depressing a single shift key.

While I have shown a particular form of embodiment of my invention, I am aware that many minor changes therein will readily suggest themselves to others skilled in the are without departing from the spirit and scope of the invention. Having thus described my invention, what I claim as new and desire to protect by Letters Patent is:

In a typewriter having a. frame, a carriage movable in the frame and a platen movable with the carriage, the combination of a plurality of key actuated type levers, type-heads carried by the type levers, said platen and type heads being relatively shiftable transversely to the direction of movement of the carriage, said type-heads cach carrying a single type character arranged to print in one relative shift position of the platen and type-heads and a pair of type characters arranged to print simultaneously in another relative shift position of the platen and type-heads. an escapement mechanism for the carriage. means including a shift lever for relatively shifting the platen and type heads, and means controlled by the shift lever and interposed between the type levers and the escapement mechanism for selectively actuating thelatter once or twice upon actuation of the type levers, said last named means comprising a plurality of toggles operatively connected with the escapement mechanism, and adapted to be actuated by the type levers, certain of said toggles being movablr` into operative position by the shift lever simultaneously with movement of the other of said toggles into inoperative position, one of the toggle mechanisms transmitting a single impulse to the escapement device upon movement of the typelever to printing position and the other toggle mechanism embodying means to 'transmit an impulse upon movement of the type-lever to printing position and a second impulse upon movement of the type-lever from printing position.

HALLA M. HARRISON. 

